Hi Maximo. Totally agree with you !
I designed and built my first phasing unit back in the late 70's for a
pair of 40m verticals. The rejection capabilities were nothing short of
incredible. Somewhat recently I used the identical unit for a modified
shorty-40 that was a joy to use. I recall back in the 70's & 80's I had
so many on the air requests for details that I wrote up a primitive 7-8
page description of the system detailing some phasing requirements and
practical parts selections. I remember making well over 50 copies of
those pages and mailed them out to anyone who wanted a copy. It was a
bit overwhelming but I was glad so many others would have the chance to
make their own unit.
Here is the very first YT video I had ever made (so forgive the
absolutely corny music) that provides some on the air demonstrations of
it's capability.
https://www.youtube.com/watch?v=UCrwEzQ9d0M&t=201s
Gedas, W8BYA EN70JT
Light travels faster than sound.....
This is why some people appear bright until you hear them speak.
On 11/17/2024 9:47 AM, Máximo EA1DDO_HK1H wrote:
Hi Stan,
I would suggest, instead of cutting pieces of coax to test different phases, use a
"Phaser":
https://www.k5ua.com/technical.htm
You can easily convert an antenna tuner into a "Antenna Phaser" and enjoy the
best out of your antennas.
73, Maximo EA1DDO
________________________________
De: TowerTalk<towertalk-bounces@contesting.com> en nombre de Stan
Stockton<wa5rtg@gmail.com>
Enviado: viernes, 15 de noviembre de 2024 22:38
Para:TowerTalk@contesting.com <TowerTalk@contesting.com>
Asunto: [TowerTalk] In phase?
A little dilemma - I just put up another tribander at ZF9CW on my new tower. I
originally had two smaller tribanders on a separate tower. I had built two
identical chokes and they have another torroid across the feedpoint that would
electrically ground both sides of all three driven elements to the boom for
additional top loading for my 160m shunt feed.
When I took the smaller antennas down I did a little work on the balun - re-soldered
some connections, etc. I don’t think I changed which side of the element the
center conductor would be attached to but cannot be 100% positive.
Now, I decided to make another large tribander and built a swing arm so I can rotate
it and have the other balun on it. I know I didn’t change that balun. The
antennas are at 78 and 47 feet. I am seeing some S Meter readings when switching
between, upper, lower, both that make me wonder whether I actually have them 180
degrees out of phase instead of in phase.
I could add an electrical half wavelength of coax for one band and evaluate it over
time, with and without that extra coax in line with one antenna and try to determine
what I’ve got. Would it be good enough to call CQ on 15m, look at the RBN for
JA spots and then insert a half wavelength of coax for 15m and do it again comparing
the results and assume that in phase would be the better of the two?
I don’t want to do what would be necessary to reach the balun on the top
antenna which is out about 8 feet. That choke across the feedpoint makes it
impossible for me to just use a piece of aluminum tubing as an extended lead from an
ohm meter to tell what is what. I could more easily tilt the lower one up and get to
the balun to change it if I knew for sure they were currently out of phase.
What I’m looking for from the experts is the best way to determine whether
these antennas are in phase or out of phase without a lot of guesswork or info on how
I could best flip the phasing 180 degrees for all three bands. I would not
necessarily know which was which but have the ability to flip it 180 degrees from
wherever it currently is.
Thanks…Stan, ZF9CW
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